Sink



FIG. 1 is a front perspective view of the sink;

FIG. 2 is a rear perspective view of the sink;

FIG. 3 is a top view of the sink;

FIG. 4 is a front view of the sink;

FIG. 5 is a side view of the sink; and,

FIG. 6 is a bottom view of the sink. 

CLAIM The ornamental design for a sink, as shown. 